level: applies to a horizontal surface that lies on a line parallel with the horizon: the vast prairies are nearly ~.  (prairie北美等地大草原)


flat: applies to any surface devoid of noticeable curvatures, prominences or depressions: the work surface must be totally ~.


plane: applies to any real or imaginary flat surface in which a straight line between any two points on it lies wholly and continuously within that surface: the ~ sides of a crystal.


even: applies to a surface that is noticeably flat or level OR to a line that is observably straight: trim the hedge so that it is ~.


smooth: applies to a flat or even surface especially free of irregularities: a ~dance floor. (平整舞池)


flush: applies to a surface or line that forms a continuous surface a line with another surface or line: the river's surface is now ~ with the top of the banks.


level水平: 水平的平面（经过一条和地平线平行的直线，这是纯解释没必要译出），flat平面: 任何没有弯曲凹凸的表面，plane平面: 意思相同属于术语，表示平面上任何两点形成的直线都包含在该平面，even平整: 可以形容平面或直线，smooth平整(最好不要说成平滑smooth本身没有滑的意思): 表示平面没有不规则，flush齐平的: 齐平是指平面或直线和其他平面或直线构成平面或直线。


记忆方法: 1）首字母SELF FP自己抚平<==要想平整。


         2）谚语a smooth sea never made a skillful mariner平静的海面打造不出优秀的水手。


        3）平整的意思是表面没有弯曲凹凸等不规则mean having a surface without bends, curves, or irregularities, and with no part higher than any other.